The term 'Cousin of -trix' can be solved by the crossword solutions ENNE (4 letters), ETTE (4 letters), and ESS (3 letters). ENNE is a French feminine name derived from the Latin word 'annus, ' meaning year. ETTE is a French diminutive suffix, often used to indicate endearment or smallness. ESS is a German suffix that is used to form nouns from adjectives. All three solutions refer to female relatives of -trix, such as a niece, granddaughter, or cousin.